app.py

# app.py
from __future__ import annotations
import os
import traceback
import regex as re2
from typing import List, Tuple, Dict, Any

import gradio as gr
import pandas as pd

# New additions for data analysis agent
from langchain.agents.agent_types import AgentType
from langchain_community.chat_models import ChatCohere
from langchain_experimental.agents.agent_toolkits import create_pandas_dataframe_agent

# ---- Local modules
from settings import (
    HEALTHCARE_SETTINGS, GENERAL_CONVERSATION_PROMPT, USE_SCENARIO_ENGINE, DEBUG_PLAN,
    COHERE_MODEL_PRIMARY, COHERE_TIMEOUT_S, USE_OPEN_FALLBACKS
)
from audit_log import log_event
from privacy import safety_filter, refusal_reply
from data_registry import DataRegistry
from upload_ingest import extract_text_from_files
from healthcare_analysis import HealthcareAnalyzer
from scenario_planner import parse_to_plan
from scenario_engine import ScenarioEngine
from rag import RAGIndex
from llm_router import generate_narrative, cohere_chat, open_fallback_chat, _co_client, cohere_embed
from narrative_safetynet import build_narrative


# ---------------- Utilities ----------------
def _sanitize_text(s: str) -> str:
    if not isinstance(s, str):
        return s
    # remove non-printing/control chars except newlines & tabs
    return re2.sub(r'[\p{C}--[\n\t]]+', '', s)


def _dataset_catalog(results: Dict[str, Any]) -> Dict[str, List[str]]:
    """Simple catalog of dataset columns for the planner prompt; dynamic & scenario-agnostic."""
    cat: Dict[str, List[str]] = {}
    for k, v in results.items():
        if isinstance(v, pd.DataFrame):
            cat[k] = v.columns.tolist()
    return cat


def is_healthcare_scenario(text: str, has_files: bool) -> bool:
    """
    Dynamic detection: require uploaded files AND either structured scenario sections
    or healthcare keywords (configured in settings).
    """
    t = (text or "").lower()
    kws = HEALTHCARE_SETTINGS["healthcare_keywords"]
    structured = any(s in t for s in ["background", "situation", "tasks", "deliverables"])
    return has_files and (structured or any(k in t for k in kws))


def _append_msg(history_messages: List[Dict[str, str]], role: str, content: str) -> List[Dict[str, str]]:
    return (history_messages or []) + [{"role": role, "content": content}]


def ping_cohere() -> str:
    """Lightweight health check against Cohere (embeddings call)."""
    try:
        cli = _co_client()
        if not cli:
            return "Cohere client not initialized. Is COHERE_API_KEY set?"
        vecs = cohere_embed(["hello", "world"])
        if vecs and len(vecs) == 2:
            return f"Cohere OK ✅ (model={COHERE_MODEL_PRIMARY}, timeout={COHERE_TIMEOUT_S}s)"
        return "Cohere reachable, but embeddings returned no vectors."
    except Exception as e:
        return f"Cohere ping failed: {e}"


# ---------------- Core handler ----------------
def handle(user_msg: str, history_messages: List[Dict[str, str]], files: list) -> Tuple[List[Dict[str, str]], str]:
    """
    One entrypoint for both healthcare scenarios and general conversation.
    - NEW: If files are uploaded, a data-aware agent is used to perform analysis.
    - Scenario mode (no files): planner -> deterministic executor -> LLM narrative (Cohere).
    - General mode: direct to Cohere with a light system prompt.
    """
    try:
        # Safety filter for user input
        safe_in, blocked_in, reason_in = safety_filter(user_msg, mode="input")
        if blocked_in:
            reply = refusal_reply(reason_in)
            new_hist = _append_msg(history_messages, "user", user_msg)
            new_hist = _append_msg(new_hist, "assistant", reply)
            return new_hist, ""

        file_paths: List[str] = [getattr(f, "name", None) or f for f in (files or [])]

        # --- NEW LOGIC: Activate data agent if files are uploaded ---
        if file_paths:
            try:
                # Load the first uploaded CSV into a pandas DataFrame.
                df = pd.read_csv(file_paths[0])

                # Initialize the Cohere Chat LLM for the agent
                llm = ChatCohere(model=COHERE_MODEL_PRIMARY, temperature=0)

                # --- AGGRESSIVE PROMPT ENGINEERING FIX ---
                # This new prefix explicitly forbids the LLM from outputting an Action and a Final Answer simultaneously.
                AGENT_PREFIX = """
You are a data analysis agent. You have a pandas dataframe named `df`.
You MUST respond in one of two formats.

FORMAT 1: To perform a task. Your response must be a single block of text with ONLY these three sections:
Thought: Your step-by-step reasoning.
Action: python_repl_ast
Action Input: The Python code to run.

FORMAT 2: To give the final answer. Your response must be a single block of text with ONLY these two sections:
Thought: I can now answer the user's query.
Final Answer: The complete answer.

CRITICAL RULE: NEVER, EVER, combine `Action` and `Final Answer` in the same response. Choose one format.
Begin by analyzing the user's query and provide your first thought and action using FORMAT 1.
"""

                # Create the pandas DataFrame agent with our new, stricter prefix
                agent = create_pandas_dataframe_agent(
                    llm,
                    df,
                    agent_type=AgentType.ZERO_SHOT_REACT_DESCRIPTION,
                    verbose=True,
                    allow_dangerous_code=True,
                    handle_parsing_errors=True,
                    prefix=AGENT_PREFIX
                )

                # Run the agent with the user's scenario text.
                reply = agent.run(safe_in)
                reply = _sanitize_text(reply)

            except Exception as e:
                tb = traceback.format_exc()
                log_event("agent_error", None, {"err": str(e), "tb": tb})
                reply = f"An error occurred while analyzing the data: {e}"

        # --- ORIGINAL LOGIC: Fallback for scenarios without files or general chat ---
        elif is_healthcare_scenario(safe_in, bool(file_paths)) and USE_SCENARIO_ENGINE:
            registry = DataRegistry()
            rag = RAGIndex()
            try:
                ing = extract_text_from_files(file_paths)
                rag.add(ing.get("chunks", []))
            except Exception as e:
                log_event("rag_ingest_error", None, {"err": str(e)})

            analyzer = HealthcareAnalyzer(registry)
            datasets = analyzer.comprehensive_analysis(safe_in)
            catalog = _dataset_catalog(datasets)
            plan = parse_to_plan(safe_in, catalog)
            structured_md = ScenarioEngine.execute_plan(plan, datasets)
            rag_hits = [txt for txt, _ in rag.retrieve(safe_in, k=6)]
            narrative = generate_narrative(safe_in, structured_md, rag_hits)

            if not narrative or "Unable to generate narrative" in narrative:
                narrative = build_narrative(
                    scenario_text=safe_in, datasets=datasets, structured_tables=None,
                    metric_hints=["surgery_median", "consult_median", "wait", "median", "p90", "90th"],
                    group_hints=["facility", "specialty", "zone", "hospital", "city", "region"],
                    min_sample=5
                )

            debug_note = f"\n\n> **Planner note:** {getattr(plan, 'notes', '')}" if DEBUG_PLAN and getattr(plan, "notes", None) else ""
            reply = _sanitize_text(f"{structured_md}\n\n# Narrative & Recommendations\n\n{narrative}{debug_note}")

        else:
            # General conversation mode (no files, not a structured scenario)
            prompt = f"{GENERAL_CONVERSATION_PROMPT}\n\nUser: {safe_in}\nAssistant:"
            reply = cohere_chat(prompt) or open_fallback_chat(prompt) or "How can I help further?"
            reply = _sanitize_text(reply)

        # Append interaction to chat history
        new_hist = _append_msg(history_messages, "user", user_msg)
        new_hist = _append_msg(new_hist, "assistant", reply)
        return new_hist, ""

    except Exception as e:
        tb = traceback.format_exc()
        log_event("app_error", None, {"err": str(e), "tb": tb})
        new_hist = _append_msg(history_messages, "user", user_msg)
        new_hist = _append_msg(new_hist, "assistant", f"A critical error occurred: {e}\n\n{tb}")
        return new_hist, ""


# ---------------- UI ----------------
with gr.Blocks(analytics_enabled=False) as demo:
    gr.Markdown("## Canadian Healthcare AI • Cohere API • Scenario-Agnostic • Deterministic Analytics")

    with gr.Row():
        chat = gr.Chatbot(label="Chat History", type="messages", height=520)
        files = gr.Files(
            label="Upload Data Files (CSV recommended)",
            file_count="multiple",
            type="filepath",
            file_types=HEALTHCARE_SETTINGS["supported_file_types"]
        )

    msg = gr.Textbox(label="Prompt", placeholder="Paste any scenario (Background / Situation / Tasks / Deliverables) or just chat.")
    with gr.Row():
        send = gr.Button("Send")
        clear = gr.Button("Clear")
        ping_btn = gr.Button("Ping Cohere")
    ping_out = gr.Markdown()

    def _on_send(m, h, f):
        h2, _ = handle(m, h, f or [])
        return h2, ""

    send.click(_on_send, inputs=[msg, chat, files], outputs=[chat, msg])
    msg.submit(_on_send, inputs=[msg, chat, files], outputs=[chat, msg])
    clear.click(lambda: ([], "", None), outputs=[chat, msg, files])
    ping_btn.click(lambda: ping_cohere(), outputs=[ping_out])

if __name__ == "__main__":
    if not os.getenv("COHERE_API_KEY"):
        print("🔴 COHERE_API_KEY environment variable not set. Application may not function correctly.")

    log_event("startup", None, {
        "cohere_key_present": bool(os.getenv("COHERE_API_KEY")),
        "cohere_model": COHERE_MODEL_PRIMARY,
        "open_fallbacks": USE_OPEN_FALLBACKS,
        "timeout_s": COHERE_TIMEOUT_S
    })
    demo.launch(server_name="0.0.0.0", server_port=int(os.getenv("PORT", "7860")))